Despite greater comorbid conditions, patients with obesity benefited as much as patients with normal body mass index (BMI) from iliac vein stent placement for proximal venous outflow obstruction (PVOO) in a study from a research group in New York. Jinseo Kim (Icahn School of Medicine at Mount Sinai, New York, USA) presented the study findings at this year’s Society for Vascular Surgery (SVS) Vascular Annual Meeting (VAM 2022; 15–18 June, Boston, USA).
Kim and colleagues outline in an abstract that it was their aim to determine the role of BMI in iliofemoral vein stent placement among patients who are normal weight, overweight, and those with obesity.
In order to achieve this, the research team retrospectively analysed a clinical registry of 624 patients who underwent iliofemoral vein stenting for chronic PVOO from 2011 to 2021. The team divided patients into three groups based on their BMI: normal (n=250, 18.5≤BMI≤25), overweight (n=249, 25≤BMI≤30), and obese (n=125, BMI≥30).
Among patients with PVOO undergoing vein stent placement, Kim informed VAM attendees that the prevalence of obesity was 20% (n=125) and overweight was 39.9% (n=249) with mean BMIs of 35.3kg/m2 and 27kg/m2, respectively.
The presenter noted that diabetes (normal: 16% vs. overweight: 22.5% vs. obese: 40.8%; p<0.001), hypertension (40.8% vs. 75.2% vs. 52.6%; p<0.001), coronary artery disease (CAD; 7.6% vs. 26.2% vs. 9.3%; p<0.001), cancer history (10.4% vs. 19.2% vs. 9.6%; p=0.017), and mean Clinical, Etiological, Anatomical, and Pathophysiological (CEAP) class (3.4 vs. 3.7 vs. 3.5; p=0.017) differed significantly across the three groups.
Univariate logistic regression, Kim revealed, showed that obesity was associated with increased risk of major reintervention (odds ratio [OR], 1.88; 95% CI, 1.13–3.06; p=0.013). The speaker added that, after controlling for age, gender, CAD, race/ethnicity, and diabetes status, the association between obesity and major reintervention became no longer significant (OR, 1.06; 95% CI, 0.5–2.17; p=0.882).
Furthermore, he communicated that log-rank test similarly showed no difference in reintervention-free survival for major or minor reoperations among those who were of normal, overweight, or obese BMI (p=0.4).
Finally, the presenter noted that improvement in mean Venous Clinical Severity Score (VCSS) composites preoperatively to postoperatively (p=0.802), one-year follow-up (p=0.111), and five-year follow-up (p=0.44) showed no differences across the three groups.
He summarised that patients classified as being either overweight or obese were prevalent among vein stent patients. Kim added that, after controlling for the risk factors associated with greater comorbid conditions, patients with obesity benefited as much as patients with normal BMI from iliac vein stent placement for PVOO, as reflected in similar improvement in VCSS composite scores.
“Obesity does not impact iliofemoral stent outcomes,” Kim concluded, adding that the procedure “should remain as a viable treatment option for those who have higher BMI and those with obesity”.
In the discussion following Kim’s presentation, moderator Misty Humphries (University of California Davis Health, Sacramento, USA) questioned how these findings might change practice. Kim responded: “I think obesity is very prevalent among the U.S. population, and providing a solid option of treatment for those patients who have a higher BMI is very important.”
One delegate commented from the floor that it is “very comforting” to know that patients with obesity can get the same benefit as that demonstrated in prior randomised controlled trials for this type of procedure.
Another delegate expressed some caution, however, stressing that “we need to be careful with reintervention” in this patient group, because obesity “cuts out the open option,” and multiple endovascular interventions “may compromise long-term outcomes.”
Speaking to Venous News, senior author Windsor Ting (Mount Sinai Health System, New York, USA) responded to this concern: “Reintervention we found to be an excellent option to extend the benefits and outcomes of vein stenting among these patients. Very few vascular surgeons resort to an open option in this disease.”